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1999 c230 lost power while accelerating

1K views 8 replies 3 participants last post by  Vaka 
#1 ·
i had to give it some pedal to get up to par with traffic. Normally i have no issues and it accelerates really good for 232,xxx miles. this time, i pretty much floored it from doing about 20 or 30 mph. The rpm's spun up to about 5500 i am guessing, and the car just felt like it was getting ready to unleash the fury, then it shifted abruptly and jerked a few times.

now it feels like it has a vacuum leak or something when i give it gas. if i grandma it, it accelerates normally, if i floor it, it just doesnt really go anywhere.

so i get home, check the codes, pulled this:

P0100 Mass or Volume Air Flow A circuit


side note: (i do believe my conductor plate needs replacing, and that may be why the rpm's revved up like that, cause it has revved up like this before but just shifted hard and continued accelerating.)


should i start with checking all the hoses or is this electrical?
 
#2 ·
this morning it started right up and then stalled,. it runs fine unless I floor it but it also stalled out twice at a red light. I cannot get the code to disappear it keeps coming back I don't even think it disappears at all to begin with. Do you think disconnecting the battery for 10 minutes will fix this or did I short out the MAF by flooring it and also having a bad conductor plate?
 
#3 ·
Do replace your conductor plate, that's what is giving you your shifting issue. Your code seems to indicate that the mass airflow sensor is faulty. Do not cheap out on this sensor, get the Genuine Bosch sensor ONLY. It's expensive, but it will end up paying for itself eventually because your engine will be running properly.

If the engine can't read how much air is going in, how's it supposed to know how much fuel to put in?
 
#4 ·
thanks for the reply, I am not too worried about replacing the MAF, I am just curious what exactly happened? Did the high rpms short out the MAF and that's why it just stopped working in a split second... On another note, I explained what happened to a mechanic at a foreign car shop, and when I mentioned that the supercharger isn't engaging now, he said it sounds like its in limp mode because of the conductor plate...... But I still have all my gears and its still drivable, just with about 50% less power
 
#5 · (Edited)
so i just cleaned out the MAF real good, erased the code, drove it around the block- and its doing the same thing. i can hear the supercharger in first and second, maybe even third if i am very light with the pedal, but if i punch it (even a little), its as if it's a normal 4 cyl.

is there more than one kind of "limp mode", that would cause the supercharger to not engage, but still allow me to drive and shift normally unless under load? and why is the only code thats popping up P0100?

(no missfire codes, and my stftrm1 and stftrm11(?) are both showing between -15 and -25)

i cant seem to find much any information at all in the past two days on this. also what is "mass or volume air flow "A" circuit"?
 
#6 ·
Cleaning MAFs doesn't do anything, these are hot film MAFs, once they are shot they are shot, no amount of cleaning will fix that. It's possible your died from old age. The reason why it's referring to "A" circuit is that ME-SFI is a very flexible fuel injection system that can be used on straight or V engines. If you'd have a V engine, you'd have a "B" circuit aswell.
 
#8 · (Edited)
bad maf shouldn't cause those transmission issues. but bad maf do throw up weird codes.

you should have replaced your maf twice by now. they last about 80-100k. i once tried a cheapo beck/arnly one. didn't seem to work right. amazon sells OEM and sometimes cheap. mine was $120.

you should start looking into patman's recommended. he certainly knows his sh!t
 
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